It has been known to provide both truck skates and in-line or tandem skates with cushioned or resilient mounting between the wheels and frame in order to absorb at least a portion of the shock received by the wheels in travel over an irregular surface.
For example, for cushioning standard roller or truck skates, Gray U.S. Pat. No. 4,403,784 describes a frame with eccentric cushioning members having wheel axle receiving apertures closer to the lower end; Ware U.S. Pat. No. 3,087,739 describes skate wheels mounted to the frame by an axle extending through a pair of circular cushions; and Wooley U.S. Pat. No. 2,726,873 describes a skate having trucks attached to the frame via cushioning blocks.
For cushioning tandem or in-line skates, Moats U.S. Pat. No. 5,277,437 describes a frame with a slot for movement of the end of a wheel axle mounted between, e.g., a pair of opposed compression springs. The patent specification suggests that the angular position of the slot is adjustable by rotation of the slot portion within the sleeve, and that the spring compression is adjustable by means of screws shown extending through the sleeve; Charron et al. U.S. Pat. No. 5,330,208 describes a wheel axle with opposite ends mounted in eccentric slots in the frame, pressed towards the lower ends of the slots by compression springs; Carlson U.S. Pat. No. 3,963,252 describes a compression spring suspension mounted in the frame, which presses the opposite ends of the wheel axle toward the lower end of opposed slots; Moats (mentioned above) and Hammill et al. U.S. Pat. No. 4,666,168 both describe use of a resilient axle sleeve and/or resilient bearing sleeves provided to allow shifting movement of the wheel, e.g. during turning; and Shim U.S. Pat. No. 4,711,458 describes a skate frame supported upon the wheel axle bearings by arcuate dampening pads.